# An Intraoperative Encounter With Langer’s Axillary Arch and Its Clinical Significance

## TL;DR

This paper describes a rare muscle found during surgery and explains why recognizing it is important to avoid complications.

## Contribution

The paper highlights the clinical significance of identifying Langer’s axillary arch during axillary surgery.

## Key findings

- An aberrant muscle slip was identified originating from the latissimus dorsi and inserting into the pectoralis major.
- Failure to recognize LAA can lead to suboptimal regional control and neurovascular injuries.

## Abstract

Langer’s axillary arch (LAA) is the most common accessory muscle encountered during axillary surgery. We present a 55-year-old lady who underwent a right wide local excision and sentinel lymph node biopsy. Intraoperatively, we identified an aberrant muscle slip traversing the axilla, anterior to the neurovascular structures. It originated from the latissimus dorsi muscle and inserted into the pectoralis major. This report explores the current knowledge of LAA and discusses the importance of recognising it intraoperatively in the era of minimisation of axillary surgery. Implications of failing to recognise it include suboptimal regional control, compromised oncological treatment, or neurovascular injuries.